I ordered early this morning, but now am having second thoughts about switching from AT&T to Verizon - mainly due to cost and better employee discount through AT&T. Can I call and cancel my pre-order and do a new order with AT&T? Also, am I going to still be able to order two iPhones with AT&T and still have them delivered on 10/14? I realize I'd be giving up some priority canceling my previous order. Thanks!